Somehow, colorful tropical scarlet macaws from tropical Mesoamerica – the term anthropologists use to refer to Mexico and parts of northern Central America – ended up hundreds of miles north in the desert ruins of an ancient civilization in what is now New Mexico.

Early scientists began excavating the large Pueblo settlements in Chaco Canyon in northwestern New Mexico and found the birds’ remains in the late 1890s,, but only recent radiocarbon dating of the physical evidence has pushed back the time period of sophisticated Pueblo culture by at least 150 years, according to a paper published today in the Proceedings of the National Academy of Sciences.

Co-author and archaeologist Stephen Plog, the University of Virginia’s David A. Harrison Professor of Anthropology, worked with Adam S. Watson of the American Museum of Natural History, Douglas J. Kennett of Pennsylvania State University and a team of researchers from the museum and other universities to have macaw bones dated and interpret the results.